ByGordon Lubold, Staff writerJanuary 13, 2010

In this Jan. 12 photo provided by the US Navy, the aircraft carrier USS Carl Vinson departs from the Naval Station in Norfolk, Va. The aircraft carrier is expected to reach Haiti by Thursday afternoon, after loading up with relief supplies at a depot in Mayport, Fla.

Washington — The US government has begun to mobilize what is likely to become a massive humanitarian relief effort to deal with Haiti earthquake damage, rerouting an aircraft carrier and other ships, using aerial reconnaissance planes, and sending assessment teams to arrive later Wednesday.

The aircraft carrier USS Carl Vinson is expected to reach Haiti by Thursday afternoon, after loading up with relief supplies at a depot in Mayport, Fla., Pentagon officials say. A number of other ships, including the USNS Comfort hospital ship and a group of amphibious ships with a Marine Expeditionary Unit aboard, are on standby and may leave for Haiti in the next few days. In addition, the US Coast Guard has deployed a number of cutters that were already in the region, officials say.

But significant challenges loom. The main airport runway is in decent shape but for now will offer limited ability to absorb the massive amount of airlifted aid, said Gen. Douglas Fraser, head of US Southern Command in Miami, during two briefings of reporters Wednesday in Washington.

Meanwhile, the Defense Department is sending at least one assessment team of 25 individuals plus a dozen or so medical and other experts, who are due to arrive Wednesday. And a P-3 Orion reconnaissance plane is being used to create a more accurate picture of the devastation.

Haiti’s temblor, with a magnitude of 7.0, hit near the capital of Port-au-Prince Tuesday afternoon. Some have described the scene as reminiscent of the aftermath of the 9/11 attacks in New York. Hundreds of thousands of people could be dead, Haitian officials say.

According to the estimates of relief organizations, as many as 3 million people could be affected – about a third of the country’s population.

“This is a significant effort across the board,” Fraser said. But much is still unknown. “The bottom to it is we don’t have a clear assessment right now of what the situation on the ground is, what the needs within Port-au-Prince are, [and] how extensive the situation is,” he said.

The international response has been fairly immediate, but US officials are still mainly in assessment mode. It is important, Fraser said, to get a good sense of what is needed before sending assets that may be unnecessary.

If Haitians grow more desperate, there could be the threat of civil unrest, which would further challenge the country’s stability.

As many as 2,200 marines with a Marine Expeditionary Unit at Camp Lejeune, N.C., could be sent on the large-deck amphibious assault ship USS Bataan, depending on the results of the initial assessments, defense officials say. Also, an Army brigade with the 82nd Airborne Division, Fort Bragg, N.C., is on call for whatever security situation could develop.

Fraser said that his deputy commander, Lt. Gen. P.K. “Ken” Keen, happened to be in Haiti when the quake hit. Keen has reported that the capital is reasonably calm but that US military officials are closely watching the security aspects of the crisis.

“We’re very seriously looking at that,” Fraser said.

Earlier Wednesday, President Obama said that the US government was preparing to respond in a significant way to what is probably one of the biggest natural disasters in recent times.

The US Agency for International Development (USAID), which has been designated as the lead American agency for Haiti relief, said that two urban search-and-rescue units – one from California and another from Virginia, with 72 individuals each – are headed to Haiti. “We are committed to a significant effort,” said Rajiv Shah, USAID administrator.

The US military has 63 Americans assigned to Haiti. They had not all been accounted for, Fraser said.